Power Play: 3 defensive tips for your portfolio

Traders work on the floor of the New York Stock Exchange.
Brendan McDermid | Reuters
Traders work on the floor of the New York Stock Exchange.

The Dow and S&P 500 have rallied 8 percent since the lows of February 11, while the Nasdaq has surged 10-percent. Because of these huge gains, Richard Weiss, senior portfolio manager at American Century Investments, tells CNBC's "Power Lunch" on Tuesday market valuations look unattractive right now.

He thinks the bull market is 'long in the tooth' by any measure and is not blindly buying on the dips.

"Re-examine your diversification – is it sufficient and suiting your needs? Reposition stock and bond portfolios," Weiss said.

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He believes investors should curtail downside risk in their equity income and re-adjust their bond funds. "Avoid risky, equity-like 'multi-sector' bond funds that have done so well in the past few years," Weiss said.

It's also a good idea for investors to protect their investments. "Purchase VIX insurance where feasible as a relatively cost-efficient market hedge," Weiss said.

The Dow, S&P 500 and Nasdaq are down slightly during trading.